Gamma-glutamyltransferase levels as a predictor of mortality in patients with ST-elevation myocardial infarction

Purpose: Gamma-glutamyltransferase (GGT) is a well known prognostic marker in patients with cardiovascular disease. Aim of this study is to define the role of GGT levels as a predictor of mortality in patients with ST-elevation myocardial infarction. Methods: 1172 patients (male: 871, 74%; mean age: 65.8±12.5) admitted for STEMI and undergoing early revascularization were enrolled. We excluded patients with cardiogenic shock and known hepatic disease (n=117). According to lnGGT measured at hospitalization, our population was divided in two groups: Group A, characterized by lnGGT levels> 3.37 and Group B characterized by GGT<3.37. Follow-up (mean: 25.5±18.5 months) started at hospital admission and was interrupted in the case of cardiovascular or other cause death. Results: Group A patients had higher aspartate transaminase (102, 50-205 vs 93, 46-186; P <0.001), alanine transaminase (35, 23-53 vs 28, 19-44; P<0.0001), creatinine (0.94, 0.8-1.1 vs 0.91, 0.8-1.2; P<0.001), glucose (115, 97-150 vs 113, 98-145; P<0.05), C-reactive protein (0.59, 0.25-1.72 vs 0.51, 0.22-1.37; P<0.05), and fibrinogen levels (283.3, 237.9-359.0 vs 281.8, 241.9-328.1; P<0.0001). Cumulative survival was significantly reduced in group A patients (log-Rank test, P<0.003). At multivariate regression analysis, age (HR 1.97, P<0.001), lnBNP (HR 1.51, P=0.02), and lnGGT (HR 1.3, P=0.02) resulted the only predictors of all cause death. Conclusions: GGT levels are a predictor of all cause mortality in STEMI patients, identifying subjects with greater inflammatory activation and worse clinical status, in spite of the absence of definite cardiogenic shock. Further studies are needed to clarify the role of GGT in this subset of patients and the necessity for more aggressive therapies.